Manufacture of methyl alcohol and other oxygenated organic compounds



Patented Sept. lg, 1931 mural) STATES PATENT oF icE IiATHIAS PIER, F HEIDIl-ILBERG, GERMANY, ASSIGNOR TO I. G. FARBENINDUSTRLE AKTIENGESELLSCHAFT, OF FRANKFORT-ON-THE-MAIN, GERMANY, A CORPORATION OF GERMANY MANUFACTURE OF METHYL ALCOHOL AND OTHER OXYGENATED ORGANIC COMPOUNDS No Drawing. Application filed February 16, 1924, Serial No. 693,372, and in Germany February 24, 1923.

Recently it has been found that methyl alcohol and other oxygenated organic compounds can be produced synthetically from mixtures of carbon monoxid and hydrogen by v the action of proper catalysts and at an elevated temperature and pressure. In practically performing the said reaction, the action of the catalyst often deteriorates more or less quickly, methane or higher hydrocarle bons being formed to a greater or lower degree instead of alcohols or other oxygenated compounds. Even by lining the hot reaction vessel with copper, in order to prevent a decomposition of carbon monoxid by the iron walls with the formation of a carbon deposit,

the deterioration aforementioned is not avoided.

I have found that in order to avoid the deterioration of the contact mass the hot parts as well as the less hot and cold parts of the apparatus coming into contact with carbon monoxid must be made, or covered inside with linings or coatings, of metals which are sufiiciently resistant to carbon monoxid and the temperature under the conditions of working, in order to prevent iron particles, or compounds, reaching the hot zone of the catalyst. As metals sufficiently resistant to carbon monoxide I wish to be understood; copper,

so silver, aluminum, or their alloys, or special steels with a substantial percentage of chromium, manganese, tungsten, molybdenum or vanadium, or the last-named metals alone, all of which metals are suitable for the hot parts of the apparatus. especially for the reaction Vessel, or metallic parts arranged therein,,

, such as supports for the catalytic mass, electric heating bodies, heat exchangers and so on, 'as well as for the cold parts of the appa- 40 ratus, whereas for the less hot parts and cold parts, for example the high pressure piping, also metals of a lower melting point such as zinc, tin, lead or their alloys may be used, or said parts may even be protected by non-metallic materials, for example coated with asphalt, or enamelled. Diderent metals, or alloys or coverings thereof, may be used for different parts of the apparatus.

As regards the use of aluminum, it may be added that it is only suitable Where the temperatures are not too high. The temperature up to which its use is permitted, depends to a certain degree on the pressure, more exactly speaking, on the partial pressure of the carbon monoxid, inasmuch as the temperature may be the higher the lower the pressure, or partial pressure, of the carbon monoxid is. Generally speaking, the temperature limit up to which aluminum can be used is about 550 degrees Centigrade. As to the special steels, the brand steel VQA (of the firm of Krupp) containing 20 per cent of chromium, 7 per cent of nickel, 0.27 per cent of carbon, 0.45 per cent of silicon and 0.35 per cent of manganese may be cited as an example. Such material is used with advantage for the electric heating resistance for the initial heating and, if necessary, further supplemental heating of the gas mixture. The coatings of chromium, tungsten and so on mentioned above can be produced in a satisfying manner by electro-deposition, for example electrochroming and so on.

In other respects, the performance of the catalytic process is not altered by applying the present invention.

In order to protect the walls which are eX- posed to the high pressure against the action of the hot compressed hydrogen, the invention may be combined with the lrnown suggestions for working with hydrogen under a high pressure, thus employing, for example, a coppertube surrounded with a perforated or otherwise permeable steel mantle, or employing an iron tube lined inside with a thin tube consisting of one of the aforesaid metals or coated with the latter, and simultaneously protected by a permeable steel mantle capable of resisting the pressure.

I made the invention set forth in the present application subsequent to the time that Mittasch and I, jointly, made the invention set forth and claimed in Patent No. 1,569,775.

What I claim is:

In the synthetic manufacture of methyl alcohol and other oxygenated organic compounds by the catalytic reduction of carbon monoxide at an elevated temperature and pressure, the step of carrying out the reaction 10 in an apparatus having the inner surface of both hot and cold parts consisting of a steel containing a high percentage of chromium.

In testimony whereof I have hereunto set my hand.

MATHIAS PIER. 

